The invention relates to the prevention of tangling, knotting or kinking of cords, lines and tubular conveyances, all having a tubular sheath at the outer circumference to protect or aid the conveyance within the tubular sheath.
The above mentioned cords, lines or tubular conveyances are known to get knotted or kinked when in use, such as electrical extension cords, air hoses or water hoses, unless time-consuming, distractive and sometimes laborious efforts are spent to prevent the knotting or the kinking or once the tangling, knotting or the kinking has occurred, to straighten or untangle the above noted conveyances for proper storage and for future use. As a result of the above noted tangling, knotting and kinking, the conveyances are subject to premature failure because of the material being overstressed where the kinks and knots occur. The above noted conveyances are non-elastic or substantially non-extendable.
Examples of different but related control means are described in the following patent documents:
Japanese Patent Number 64-33812, issued to Shigematsu on Feb. 3, 1989 describes four conductive wires juxtaposed adjacently to a plurality of spiral springs arranged in a rectangular shape and embedded in a core of insulating material.
U.S. Pat. No. 4,816,618, issued to Bongianni on Mar. 28, 1989, describes inner conductors in a dielectric matrix of a coaxial cable.
U.S. Pat. No. 4,629,827, issued to Baxter on Dec. 16, 1986, describes a cable having a jacket with tensile reinforcements by successive lengths of tape.
U.S. Pat. No. 4,487,641, issued to Bohannon, Jr. et al on Dec. 11, 1984 discloses a method and apparatus for a laminate shield on a rodent and light-guide cable.
U.S. Pat. No. 4,357,500, issued to Nilson on Nov. 2, 1982 is directed to an elongate member that is positioned in a portion of a telephone handset cord to prevent twisting and entanglement.
Australian Patent No. 108, 667, issued to Simon on Mar. 22, 1938, describes a flexible conductor of electricity with no provisions having been made to avoid any kinking or knotting.
U.S. Pat. No. 2,998,028, issued to Rohde on Aug. 29, 1961, describes a flexible hose or tube with one or more resilient members in its walls.
U.S. Pat. No. 2,619,126, issued to Eickmeyer et al on Nov. 25, 1952 is limited to a gasoline pump hose having a coiled leaf spring attached to an outside of the hose to induce a deliberate coiling of the Hose.
Japanese Patent No. 017,921, issued on Aug. 18, 1984 to Shiroishi et al is directed to a wiring cable for robots. The device consists of a coiled electric wire having multiple wiring conductors. The outer circumferential coil sections are covered with an elastic substance. This structure has an interior stretch inhibiter in the form of either rubber bands or a coil spring. The object of this patent is to limit the elastic extension of the basic coiled wiring within a certain range as long as it does not exceed the maximum elasticity of the interior rubber or the interior coil spring. This patent does not teach at all any arrangements to prevent tangling, knotting and/or kinking or entanglement in or of any tubular conveyances.
In view of the above noted problems, the objects of the invention are to provide a non-kinking or non-knotting or non-entanglement to elongated and substantially non-extendable cords, lines or tubular conveyances. The invention at hand does not make use of expansion and/or contraction but focuses on restriction. The present invention restricts itself to the use with a portable tubular conveyance such as portable extension cords, garden hoses, air hoses and similar conveyances which are not of a coil or curl code type construction. The present invention uses a flexible body member extending the full length of the conveyance. The flexible body is not elastic and therefore cannot be extended. It can be bent laterally at its extended length but it is resistant to any twisting. As a matter of fact, the flexible body member has a torque memory, meaning, that when any twist is introduced into the body member, it tends to forcefully return to its untwisted state. This phenomenon has been discovered after many experiments and prevents any conveyance of the above described category from kinking, knotting or entangling.
The elongate body member can be incorporated into an electrical conductor having at least two or more electrical conductors twisted or wrapped around the body member, thus acting as a core member and thereafter having an insulating sheath or tube installed or otherwise attached to the outside of the conductors. The elongated body member can take the shape of a round, square or rectangular body. It is important that the elongated body be restricted to substantially any lateral movements within the tubular conveyance so as to keep the elongated body member substantially within the center of the conveyance.
This principle equally applies to water hoses or air hoses. In this application, the elongated body member consists of a rectangular but somewhat thin body being placed within the tubular conveyance. The elongate body member is of a width to substantially span the interior wall diameter of the tubular conveyance. It can now be seen that when the tubular conveyance is subjected to any twisting, which would be the beginning of any tangling, knotting or kinking, the elongated body member resists the twisting motion and tends to return to its untwisted state because of its plastic torque memory. The more the conveyance is twisted, the more the elongated body member is torqued, the more it tends to forcefully return to its untwisted state.
Under certain circumstances, especially when applied to heavy duty water or air conveyances, the elongated member can take shape of an extruded triangular configuration whereby at least three contact points are obtained against the interior wall of the conveyance.